Do both devices have the same amount of memory? Also was iCloud backup turned on?
– TysonJan 2 '15 at 15:39

Just checking - you did it exactly as this method? support.apple.com/en-us/HT2109 edit - Google found a mumble about Win 64bit iTunes doing this more than 32bit. Mac, of course doesn't distinguish. What platform are you on?
– TetsujinJan 2 '15 at 18:25

Yes both had a memory space of 16 gb and i never had a backup of my phone on icloud.
– jerryJan 4 '15 at 4:51

Your new phone may be running an older version of iOS. Try updating/restoring it without a backup, and then restoring from your backup.
– Aaron BragerMar 2 '15 at 5:05

From that link, you can also poke around to learn more about corrupt backups if you want.

(Note: As I mentioned, I am the author of the software I'm recommending above, so I stand to benefit from my recommendations. I definitely stand behind our software :) but I like to put a little note like this anyway!)

WOW. Normally it can be distasteful when people post about their own products, but this app is fantastic and removed some stupid file that was preventing my backup from restoring to my phone. Now I have all my stuff back. Thanks so much for making this.
– AriXApr 24 '15 at 21:20

1

Agree with the comment above. I got stuck with this error after years and years of problem-free backups. The program solved the problem quickly and easily.
– uvestenJul 5 '15 at 20:39

1

Same situation -- iTunes backup/restore has always worked perfectly, but I ran into an issue with all my backups in the latest version. This program fixed it. Always test your backups before you need them…
– Kevin ChenSep 3 '15 at 22:26

I had the same problem, no idea where it came from. I had a jailbroken iPhone 3G and switched to a non-jailbroken iPhone 4, i.e. I transferred the backup to the new phone, which worked. Some time later, however, I got that error message. I tried the solution above, I even deleted all backups, even the ones not related to that phone, but the error persisted.

Delete everything there (or move it somewhere else, to be on the safe side)

And done. In my case, I deleted two folders with long, cryptic, alphanumeric names, one empty, the other over 1GB in size. When I opened iTunes again, I could create a brand new backup without any errors.

The following is the solution if you are getting the corrupt backup error during a sync or backup in iTunes (during a sync, the sync is just triggering a backup):

During a sync or backup, deleting the backup is the way to go, and iTunes will create a new one from scratch. However, the original poster has the additional issue that the backup isn't appearing in iTunes.

@doncherry has the correct idea -- if iTunes isn't listing your backup in the Preferences->Devices list, then you need to delete the backup manually. He has pointed out the location to look in Windows. On a Mac, the backups are stored in

/Users/<your username>/Library/Application Support/MobileSync/Backup

Open Finder, (hold the option key on OSX Lion or higher), and select Library from the Go menu. This will open the Application Support folder, and from there, go to MobileSync -> Backup. In the backup folder, there will be one or more folders named by your devices' unique identifiers.

In iTunes, click on the Serial Number in the Info tab for your device, and the Serial Number field will switch to your device identifier. Match the identifier you see there to a folder name in the MobileSync -> Backup folder. Delete that folder!

If you are getting the corrupt backup error during a restore in iTunes, clearly deleting the backup isn't going to help you get your data restored ;)!

(Clearly, I stand to benefit from the links I am posting in this answer, as the author of the software. However, I wanted to give both sides of the issue, corrupted backups during the backup process, and corrupted backups during the restore process. Anyone is also welcome to follow the links above and navigate to our support page to send us an email if you have questions about your corrupted backup. Feel free to mention my name directly: Kelly.)

I'd also like to append an easy way to get to your backup folder on various Windows OS'es: Go to Start->Run (or search on Windows 8) and type %appdata% (with the percents.) Press enter and a file browser will open to the Application Data folder for your user. Navigate to Apple Computer -> MobileSync -> Backup, and you'll see your backup folders.
– KellyAug 22 '14 at 17:00

So I copied the full "Backup" directory in another location (copied, not moved)
Then I create a new iphone with Itunes after restoring ipsw file, given the same name as it has previously.

I did a sync+backup.

At the end I checked the "Backup" directory and saw that Itunes recreated the same folder as the one I had copied earlier.

This time in Ituens when I right click my iphone, I have the menu "restore from backup". But before select this option, I just renamed the new created directory in Backup to xxx.old , and copy back the saved one (the one with same name) into the C:\Documents and Settings\franckca\Application Data\Apple Computer\MobileSync\Backup directory.

I also ran into this issue. Turns out after I made the backup of my iPhone, Windows defender detected a file from one of the apps that I had downloaded as a malware. When I looked into the file, it indeed was a malware however removing it from the back up directory cause the restoration process to fail repeatedly.

It wasn't until I restored the file back in the backup directory that the restoration completed successfully. I would highly recommend to disable antivirus and malware detection programs while doing iPhone backup and restoration.

I had this issue also, but there were no backups listed in Preferences. My solution revolved around not having my external hard drive connected, which is where iTunes was storing my iPhone backup files. Connecting the hard drive solved the issue.

I've had this happen 2-3 times in the last few years when doing processor intensive tasks while iTunes was backing up my phone. Deleting the corrupt backup, rebooting the computer and backing up the iPhone again took care of the problem.

Thank you for your interest in this question.
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